Preserving rubber



Patented Oct. 18, 1938 UNITED STATES PAT This invention relates ber.

compounds falling within the scope of the in- V p c vention and embracing specieshaving substituen'ts 7 p on the ring. O CH? .ZH CVHE NHQ Following are the formulae of some representa- O H O H I tive compounds: 7 V l CH3 V .O-CH2-CH2-NH2 ,7 t-

-O OHa-CIH-CHz--NH2 7 OH I I CHa .O-CHzOHz-CHn-NH2 f CHa-NH 9 t H o-om-NH, CFCHCHFNH O CH3 v O-CHr-QHrNH'z O-OHz-CHz-CH-CH2NH2 OC.Hz-,?HNH2 c v l C2Ha HO 7 I v NH: HONH0CHzCHOHz-NH2 0- H-OHa 11 QNHQOQHT-CHTNH1 cH.C -NHONH 0-om cmNH, CH3

OOH:CHa-NH: NH-CH:CHz-NH HO O-CHr-CHr-NH2 PRESERVING RUBBER Ohio, assi'gnor-to Wingtiqn of Delaware 'No Drawing.

Serial No. 78,007

'13 Claims.

to thetreatment of rub- More particularly it relates to a method of retarding the deterioration of rubber due .to aging. This case is a continuation in part of application Serial N0. 618,087 filed June 18, 1932. Many compounds have been suggested for use in rubber as antioxidants and ag'e-resisters. By the present invention it has been'discovered that still another class of materials is suitable for this purpose. These new antioxidants may be represented by the formula R10RNH2, in which R is an alkylene group and R1 is an aryl group. This aryl group R1 may contain various substituent groups, including amino groups, the above formula representing, in a general manner, the

Application May- 5, 1936,

onl -0H2 The foregoing compounds are but a few of those comprised by the invention and are, thus merely indicative of the variations possible while still conforming to the general formula as originally stated.

The type of compound herein described for use in rubber has been mentioned in the literature and methods of preparation set forth. For example, in Beilstein, 3rd ed. (1896), Vol. II, page 877, aminoethyl naphthyl ether is described and the statement made that the compound may beprepared by heating bromethyl naphthyl ether with an alcoholic solution of ammonia at 100 C. The product is a white amorphous material. Instead of the bromo-compound, other corresponding halogen compounds, such as chlorethyl naphthyl ether, may be employed if desired. The reaction is preferably carried out under pressure in an autoclave.

Other compounds coming within the purview of the invention may be prepared in this same manner, or by other methods. In fact, any method of preparation may be followed which gives compounds of the character herein described and the invention is not limited by such methods of preparation.

The compounds may be employed with success in most of the usual compounding formulae. The following formula is one in which they have been found by test to yield excellent results:

Parts by weight Rubber (extracted pale crepe) 100 Zinc oxide 5 Sulfur 3 Hexamethylene tetramine 1 Stearic acid 1.5 Antioxidant 1 The efiiciency of these compounds is admirably illustrated by the action of beta-amino ethylbeta-naphthyl ether. This material was incorporated into rubber in accordance with the above formula and samples were cured. These samples were tested before aging and after six days aging in an oxygen bomb. The following results were obtained:

Original Aged 6 days 01 bomb Cure Tens. Elong. 500 700 Tens. Elong. 500 700 if s 35/285... 128 885 15 45 123 870 15 44 Lostwt. 5o 14s s55 18 58 138 810 19 .35 7o 800 25 93 11s 71s 29 108 Lost wt.

The antioxidant qualities of the material are indicated by a comparison of the tensile strength 0-01; on NH O r O -0-CH:-CH:-NH ..HN O-CHr-CHz-NH---------.--

of the samples before and after aging and by the low increase in weight shown, this latter being due to the oxygen absorbed during aging.

Although only the preferred forms of the invention have been described in detail, it will be apparent to those skilled in the art that various modifications may be made therein without departing from the spirit of the invention or the scope of the appended claims, in which it is intended that the patent shall cover by suitable expression in such claims, all features of patentable novelty residing in the invention.

I claim: 7

1. The method of treating rubber which comprises incorporating therein an age-resister having the formula R1O-R-NH2, in which R is alkylene and R1 is aryl.

2. The method of treating rubber which comprises incorporating therein beta-aminoethylbeta-naphthyl ether.

3. The method of treating rubber which comprises incorporating therein a primary aminoalkyl phenyl ether.

.4. The method of. treating rubber which comprises incorporating therein a primary aminoalkyl naphthyl ether.

5. The method of treating rubber which comprises incorporating therein an age-resister having the formula R1O R-NH2, in which R is alkylene and R1 is aryl and vulcanizing the same.

6. The method of treating rubber which comprises incorporating therein beta-aminoethylbeta-naphthyl ether and vulcanizing the same.

'7. The method of treating rubber which comprises incorporating therein a primary aminoalkyl phenyl ether and vulcanizing the same.

8. The method of treating rubber which comprises incorporating therein a primary aminoalkyl naphthyl ether and vulcanizing the same.

9. A rubber product in which has been incorporated an age-resister having the formula R10R-NH2, in which R is alkylene and R1 is aryl.

10. A rubber product in which has been incorporated beta-amino-ethyl-beta-naphthyl ether.

11. A rubber product in which has been incorporated a primary aminoalkyl phenyl ether.

12. A rubber product in which has been incorporated a primary aminoalkyl naphthyl ether.

13. The method of treating rubber which comprises incorporating therein an age resister having the formula R'-O-R.-NH2 in which R is alkylene and R is anaromatic radical selected from the group consisting of phenyl and naphthyl groups.

ALBERT M. CLIFFORD. 

